1. Field of the Invention
The present invention relates to machine trigger system which triggers a machine into action without operator intervention and, more particularly, to a no touch machine trigger system for a wire stripper assembly which uses a fiber optic detection system to detect the presence of the wire to be stripped and assures proper orientation of the wire before automatically triggering the stripper mechanism.
2. Description of the Prior Art
Devices are known which automatically strip the protective shielding from a wire and apply a connector thereto. Such devices require the wire to be stripped to be inserted into the stripping assembly, usually via a tapered section which guides the wire to a triggering mechanism in the target area which causes a gripper mechanism to grip and strip the wire and a connector applicator to apply a connector to the stripped wire. In the prior art, the triggering mechanism typically comprises an air trigger at the end of the target area. The air trigger includes a paddle at the end of the target area, an air hole, and a ball bearing. During operation, the wire is inserted into the target area far enough to move the paddle at the end of the target area, the paddle is moved away from the wire so as to push a ball bearing to cover the air hole, and the resulting back pressure causes the stripper assembly to be activated. Unfortunately, trigger mechanisms of this type can only be used with relatively large gauge wires since small wires may be insufficient to move the paddle and the ball bearing to trigger the stripper assembly. Also, since the paddle moves when the wire is inserted sufficiently far, it is possible that the wire will be out of alignment when the stripper assembly is actuated.
Other triggering devices for wire stripper assemblies address the above problem by using an air-cone sensor mechanism which is situated such that an inserted wire blocks the air flow so as to cause the necessary back pressure to trigger the stripper assembly. Unfortunately, such an arrangement is also dependent on the gauge of the wire, for small gauge wires may be too small to block the air flow well enough to cause enough back pressure to trigger the stripper mechanism. Also, if the wire is not cut cleanly, then the triggering device will not work properly.
In other art areas, it is generally known to use the interruption of a light signal as a trigger mechanism. For example, Hentschel et al. disclose in U.S. Pat. No. 4,598,199 a safety device for controlling a laser so that the laser is only activated when an optical fiber is connected to the laser. Connection of the optical fiber is detected by a photodetecting circuit which detects light (or stops detecting light) only when the optical fiber is coupled to the laser.
Numerous other safety devices are known which use the interruption of light to trigger machines at a time when the operator is safely away from the moving parts of the machines or to deactivate machines when the operator moves into a danger zone. However, the present inventor is not aware that any of these devices is triggered by an object being processed by the machine (i.e., an object other than a body portion of the operator) where the object is inserted into a target area for activating the machine so as to insure proper alignment of the object before actuation. The present invention is designed to meet this need in the art.
More particularly, an improved trigger mechanism for a wire stripper device is desired which is independent of the gauge of the wire and which aligns the wire in the proper orientation when the stripper mechanism is actuated. The present invention has been designed to address these needs in the art as well.